Serial library interrupt frequency.

RE: Serial library interrupt frequency.

krog1 — Fri, 30 Aug 2019 20:53:02 GMT

Kenneth, libuarte_async looks like exactly what we need for a cellular module stack we're working on. Do you know if it's been tested with FreeRTOS? I'm not looking for guarantees, and I'm happy to do the legwork to test and do some light porting, but if you know for sure it doesn't work and it ain't gonna because X, Y, and Z, that would save us quite a bit of time.

Thanks!

- Chris.

RE: Serial library interrupt frequency.

Kenneth — Wed, 12 Jun 2019 11:25:57 GMT

Alternatively I would recommend to try nrf_libuarte_async driver for UARTE and lossless reception without HWFC. There are experimental_cli_libuarte and experimental_libuarte example in the SDK that show usage. They are labelled experimental due to lack of documentation but it has been thoroughly tested. The stability and quality of the libuarte is very good. The libuarte library requires one TIMER, one RTC or TIMER, couple of PPI channels (~3 if recall correctly). It is using TIMER via PPI to count exact number of bytes received without stopping uarte.

Best regards,
Kenneth

RE: Serial library interrupt frequency.

spoologa — Fri, 23 Nov 2018 07:45:58 GMT

Thank you for that answer. That helps.

RE: Serial library interrupt frequency.

Kenneth — Thu, 15 Nov 2018 20:57:16 GMT

Hi,

The NRF_SERIAL_EVENT_RX_DATA is triggered on NRF_DRV_UART_EVT_RX_DONE, which is not the same as NRF_UARTE_EVENT_RXDRDY event. The NRF_UARTE_EVENT_RXDRDY event is not propagated to the serial_event_handler().

At 921600 baud there is a byte received every 8.6us, likely the serial_event_handler() will not be able to execute that fast in any case. If you need to know when each byte is received you need to use the uarte driver directly, instead of the serial library.

Best regards,
Kenneth